SYSTEM BOARD aka MOTHERBOARD

The system board is the main logic board in any laptop. All internal components are connected to the system board. This is one of the most expensive parts in a laptop.

MEMORY aka RAM

More memory you have installed – better the performance of the laptop.
Learn about different types of memory, compatibility issues and how you can replace or upgrade memory yourself. The memory is a user replaceable part.

HARD DRIVE

The hard drive is the main storage of information in a laptop. All system files, personal files are stored inside the hard drive. Find the difference between SATA and IDE hard drives. Faster hard drive you have installed – faster data access you get. You can upgrade the hard drive yourself.

PROCESSOR aka CPU

The processor is the brain of your laptop. Faster CPU means faster data processing.

KEYBOARD

The keyboard is the main input device. Find out how the keyboard is connected to the motherboard and how it can be removed or replaced.

CD/DVD OPTICAL DRIVE

The CD/DVD drive allows you to read/write data from/to a CD or DVD disc. Lear about the difference between drives with regular and SATA connectors.

COOLING FAN

The cooling fan is a part of the cooling module in a laptop. The fan helps to cool down the processor when the laptop is turned on.

VIDEO CARD aka GRAPHICS CARD

In most modern laptops the video card is integrated into the system board. If the video card fails you have to replace the whole motherboard.
In some laptops the video card is a discrete module and can be removed or replaced separately from the motherboard.

AUDIO BOARD aka SOUND BOARD

In most laptops the audio board is a part of the motherboard. If that’s the case, all audio board input/output components such as volume control, microphone jack and headphone jack are soldered directory to the motherboard.

WIRELESS NETWORK CARD

The internal wireless card helps you to connect to the Internet without running a cable. Learn about different types of internal wireless cards and how they are connected to the motherboard.

CMOS BATTERY aka RTC BATTERY

The CMOS battery provides power to the CMOS chip when the laptop is turned off or disconnected form the wall outlet.

LCD SCREEN

The LCD screen is one of the most expensive parts in a laptop computer. The LCD screen mounts inside the display panel.
If you accidentally cracked the screen, it has to be replaced. You cannot repair  a cracked screen.

SCREEN INVERTER BOARD aka FL INVERTER

The inverter board is a power supply for the backlight lamp inside the LCD screen. When inverter fails, the LCD screen goes very very dark and you barely can see any image on the screen. In most laptops the inverter board is mounted inside the display panel below the LCD screen.

SCREEN BACKLIGHT LAMP aka CCFL TUBE

The backlight lamp is the main source of light in the LCD screen. The backlight lamp is mouted inside the screen. When the backlight lamp fails, you have to replace the whole LCD screen. It’s possible to replace just the lamp inside the screen but it’s very hard and has to be performed by an experienced technician.

SCREEN CABLE aka VIDEO CABLE

The video cable connectes the Laptop screen to motherboard. The video cable carries data signal for the LCD screen and power for the ivnerter board.

WEB CAMERA

Many modern laptops come with a web camera built into the display panel. The web camera is not a part of the LCD screen. The web camers is located on a separate board and can be replaced separately from the LCD.

DISPLAY HINGES aka SCREEN HINGES

The dispaly hinges connect two main parts of any laptop – the display panel and base assembly.

AC/DC POWER ADAPTER

The AC/DC power adapter converts high voltage AC power from the mains to low voltage DC power required by the laptop.

MAIN BATTERY

The battery is a secondary source of power for a laptop. The battery gets charged while the laptop is plugged into the mains and keeps the laptop running when it’s unplugged from the mains.

A system board also known as motherboard or mainboard is the main circtuit board in any laptop. Unlike desktop PC system boards, laptop system boards come in thousands of different shapes and sizes. Laptop motherboards are model-specific. In other words, you cannot remove motherboard from a Toshiba laptop and stick it into a Dell laptop. All parts inside a laptop are connected to the system board, either directly via a connector mounted on the system board or through a cable.

In a typical laptop the following ports and components are permanently attached to the system board and cannot be easily removed and replaced without soldering:
1. Hard drive (HDD) connector.
2. CD/DVD drive connector.
3. Memory (RAM) slots.
4. Battery connector.
5. Keyboard connector.
6. Audio (headphone and microphone) jacks.
7. Volume control wheel.
8. USB ports.
9. Eithernet (RJ45 aka network) port.
10. IEEE 1394 (Fire Wire) ports.
11. Video chip and some other components and ports.

System board, processor (CPU) and LCD screen are the most expensive parts in any laptop. In some cases, when one of these three parts fails, it’s cheaper to buy a brand new laptop than replace the failed part. But each case is different so do your research.

The system board is mounted inside the laptop base assembly. In order to remove or replace the motherboard, you’ll have to disassemble the whole laptop.

SYSTEM BOARD FAILURE SYMPTOMS.

When a system board fails, you may experience the following most common problems with your laptop. 1. The laptop is completely dead. There are no LED light activity when you press on the power button or plug in a known good AC power adapter. 2. The laptop starts but the video output on the LCD screen or external monitor is garbled. Most likely this is related to the VGA chip failure. 3. The laptop turns on without video on the screen and the power LED starts flashing. 4. The laptop works fine with AC power adapter but will not charge a known good battery. If that’s the case, most likely there is something wrong with the battery charging circuit or DC power jack.

Display hinges connect two halves of a laptop – the display panel and base assembly. All regular laptops have two hinges located on the left and right sides of the display panel. Tablet PCs have one hinge-swivel located in the middle of the display.

The LCD screen mounts to the the screen mounting brackets which are permanently attached to the display hinges. There are two or more screws securing the LCD screen to each mounting bracket.

The display hinges are not repairable. If the hinge is broken or too loose to keep the display in an open position, you have to replace it with a new one.

On the picture below you see a laptop with removed LCD screen.

In order to remove and replace hinges, you’ll have to disassemble both, the display panel and laptop base.

HINGE RELATED PROBLEMS

1. The laptop display feels loose. It will stay in the up position, but when you move the display it feels floppy.

First of all, try tightening screws securing both hinges to the laptop base and display cover. If tightening screws doesn’t help, apparently your hinges are worn out and will have to be replaced soon.

2. The display will not stat in the up position. When you open the display and leave it in the up position, it falls back.

Most likely one or both hinges are broken and have to be replaced. Even if only one hinge is broken, I would recomment replacing both hinges because the second one is worn out and could break too in the near future.

A laptop LCD cable also known as video cable, display cable or screen cable. This cable transfers data signal from the motherboard and video card to the LCD screen. Also, most video cables supply high voltage DC power to the screen inverter.

On the picture you can see a typical laptop video cable. The cable has three ends with three connectors. One end plugs into the connector on the back of the LCD screen, the second end plugs into the inverter board, the third end plugs into the connector on the motherboard or video card.

The top part of the cable runs inside the laptop display panel between the LCD screen and display cover.

The bottom part of the cable could be found either under the keyboard or keyboard bezel.

In order to remove and replace the LCD cable, it will be necessary to disassemble the whole laptop.

LCD CABLE RELATED PROBLEMS

1. The image on the screen appears normal until you move the display up or down. When you move the display, the images on the entire screen starts to flicker, disappear or change collors. As soon as you stop moving the display, the image gets back to normal.

2. The LCD screen lights up but there is no image at all. The entire screen is blank. An external monitor connected to the laptop VGA port works fine, there is no problems with the external video output at all.

3. Image on the entire LCD screen is garbled. An external monitor works fine.

In many cases the video cable failures are very similar to the LCD screen failures.

A backlight lamp (also know as backlight bulb, screen backlight, CCFL tube or bulb) is the main and only source of light in a laptop LCD screen. A typical laptop LCD screen has only one backlight lamp installed. The backlight lamp mounts inside the laptop screen in the lower part of the screen as it outlined on the picture above.

A pair of cables with one connector coming from the screen plugs into the screen inverter board.

The backlight lamp receives high voltage AC power from the screen inverter board which receives low voltage DC power from the motherboard via the LCD screen cable as it shown on the picture below.

On the next picture you see a typical backlight lamp removed from a typical laptop LCD screen. There are two cables soldered to both sides of the backlight lamp attached to one connector.

BACKLIGHT LAMP REPLACEMENT

It is possible to replace a failed backlight lamp with a new one but it’s not easy because the backlight lamp is buried deep inside the LCD screen and it’s very easy to damage the screen during the disassembly process. This repair should be performed only by an experienced technician. You can find some home made backlight replacement instructions if you do this Google search. For inexperienced people it would be much easier to replace the whole LCD screen.

BACKLIGHT LAMP FAILURE SYMPTOMS

1. The laptop screen lights up only for a short period of time or will not light up at all. The image on the screen is so dim that you can barely see it. At the same time, an external monitor attached to the laptop works fine.

2. When you turn on the laptop, the screen works fine for a while, then start flickering and the light turns off. Again, there is a very faint image on the laptop screen and external video output works fine.

3. The screen works but the image has a reddish/pink tone. External video output works fine.

The backlight lamp failure symptoms are very similar to the inverter board failure symptoms. If you have to guess which one is causing the problem, try replacing the inverter board first.

Laptop inverter boards (also know as LCD inverter, FL inverter, screen inverter, backlight inverter) come in different shapes and sizes. On the picture above you see some typical looking inverter boards found in laptop computers.

The inverter board works as a power supply for the backlight lamp mounted inside the LCD screen. The inverter board converts low voltage DC power (few volts) supplied by the motherboard to high voltage AC power (few hundred volts) needed for the backlight lamp.

When the inverter board works properly, the backlight lamp gets power and the LCD screen lights up. As a result, the image on the screen is bright.

HOW INVERTER CONNECTED TO LDC SCREEN

On the picture below you can see a typical laptop display assembly which includes the LCD screen, video cable and inverter board.
One side of the inverter board connects to the backlight lamp and another side to the video cable (LCD screen cable).

HOW INVERTER MOUNTED INSIDE LAPTOP DISPLAY PANEL

In most laptops the inverter board is mounted below the LCD screen as it shown on the picture below. You can get an access to the inverter board when you remove the screen bezel – a plastic frame around the LCD screen.

TYPICAL INVERTER FAILURE SYMPTOMS

Usually inverters fail in one of the following ways:

1. When you turn on the laptop, the screen lights up for a short period of time and then goes dark. You still can see an image but it is very dark, almost invisible and definitely not usable. When you restart the laptop, the screen lights up and then goes dark again. The laptop works fine with an external monitor.
2. Your laptop turns on but the screen remains dark all the time. You still can see a very dim image outline. The laptop works fine with an external monitor.
3. The laptop screen works fine for hours or even days, but sometimes it goes very dark as it mentioned above. When you restart the laptop, the screen works fine again.

Inverter failure symptoms are very similar to backlight lamp failure symptoms and in most cases you cannot tell which one is causing the problem until you replace either the inverter board or the backlight lamp. From my personal experience, inverter boards fail more often than backlight lamps. If you have to guess, replace the inverter first.

A laptop screen also known as LCD screen displays an image generated by the laptop video card. The LCD screen receives data signal from the video card through the LCD cable.

Laptop screens come in many different sizes and resolutions. In order to find the LCD screen size (in inches), you’ll have to measure the screen between the two diagonal corners.

Older laptops had mostly full screen LCD displays. Newer laptops have mostly widescreen LCD displays.

A backlight lamp (also known as CCFL bulb) is the main source of light in any LCD screen. The backlight lamp powers up by the inverter board.

The LCD screen mounts inside the laptop display panel between the screen bezel and display cover. The LCD screen is attached to the screen brackets (display brackets) which are permanently attached to the display hinges.

TYPICAL LCD SCREEN RELATED FAILURES

On the following images you’ll see some typical LCD screen related failures.

1. You can see image only on a part of the LCD screen. For example, only the top side of the screen works properly.

2. There is one or more thin multi color lines running down the screen.

3. There is a wide band running down the LCD screen. The

BUYING A NEW REPLACEMENT SCREEN

The LCD screen is one of the most expensive parts in a laptop computer. If your screen is damaged and you decide to replace it yourself, you’ll have to make sure to purchase a new screen compatible with your laptop. Hear are a few things to consider before buying a new screen:

1. Screen size.
2. Some laptops come with full size LCDs. Some laptops come with widescreen LCDs.
3. LCD screen could be matte or glossy.
4. Same size LCD screens may have different resolutions.

The best way to find a new replacement screen would be using the manufacturer’s part number or LCD screen model. Both could be found on the back side of the screen.